US2930721A

US2930721A - Dishwashing method

Info

Publication number: US2930721A
Application number: US524364A
Authority: US
Inventors: John B Tuthill
Original assignee: Individual
Current assignee: Individual
Priority date: 1955-07-26
Filing date: 1955-07-26
Publication date: 1960-03-29
Anticipated expiration: 1977-03-29

Description

March 29, 1960 J. B. TUTHILL DISHWASHING METHOD 2 Sheets-Sheet l Filed July 26, 1955 ATTO/e Eg March 29, 1960 J. B. TUTHILL msx-WASHING METHOD 2 Sheets-Sheet 2 Filed July 2e, 1955 3: mm. om. md. ou. u: b: no. no. mm om nw om, E. mo ou w.6 o @SEE @.mlmozoomm z m2 INVENTOR.

Jo/w 5. 720%/7/ 'detailsi of construction.

'assenza D isHwAsnrNG METHoD Violin B. TuthilhKansas City, Mo. f I Application Jury 2,6,.i95s, serial No. 524,364

l l 5, claims. (ci. 134-25) nited States Pater pipe 42 provided with ashut-otf valve 44. Alternately, i

ffice valve 24 withinthe body 2t) has an overflow pipe 26k operably coupledrwith a solenoid V28, the pipe 26 being surrounded by a filtering ymedium such as a removableV screen 30 within the valve body 20.

A water recirculation system is employed and includes i a pump 32-driven by an kelectric motor 34 and having its inlet end vconnected with the body 2t) above the valve 24 by a line 36,`the outlet end of the pump 32 communicating-l with lthe manifold 1-6 through a line 38. Waterfrorn a supply line 40 may be introduced into the vat 10 above theoverow lineof the latter-through a the water supply may be coupled with' the line 3,6 through the medium of a Ypipe'lit having ashut-,oft' valve 48 inter-r posed therein;

A sterilizer container '54B and a container 52 for a` detergent, are connected directly with the vat lil' above the water` level in the latter for owiof materials by gravity thereinto through pipes 54 and' 56 respectively, having lt is the most important object of the instantfinvention to provide an improved dishwashing methody .that in'-A corporates water-savingfeatures by utilizing theknal rinse of each cycle of operation as the liquid medium for the washing step of the next succeeding cycle.

Another important obect of the present invention is the provision of a recirculation method forV washing dishes includingautomatically cleaning, during each cycle, the safety screen employed to` filter the circulating liquidsand prevent clogging of the various parts of the machine. i

A further important objecty of this invention is to provide in a dishwashing method, gravity ow introduction of a sterilizerand a detergent wherein the latter may either be in a powdered or liquid form.

A still further object of .this invention is to provide.

for atleast momentary discontinuance Vvof the recirculating system during'each cycle to: prevent theI possibility of air locking.

In the drawings:y

Figure 1 is a `chart showing schematically onetime schedule thatvmay be utilized in the method of washing Fig. 5. is. a side elevational Viewl of the` dishwashing c machine with. one. wall of the shell thereofl removed and parts being brokenv away and in section .toY reveal Fig. 6. is. an enlarged; fragmentary, verticalpcrosssectionaljview Ithrough the outlet conduit ofthe dish-l wasningvat; and Y Fig. 7 is a-.fragrnentary, cross-sectional view taken on line VIIe-VII of Fig. 6; v

Asshown in Figs. 2 and: 5'of',the drawings, there is provided.l a vat broadly, designated by the numeral lll' thereof terminatingin a valve body 20 that discharges to` waste by means of a drain pipe 22. A normally closed..

1 7.0; and, therefore', thediscs thereon, rotate one cycle Operation of motor 34' and, therre- ,solenoid valves interposed' therein, the solenoids where-V ofvrare designated by the numerals 5S and 60 respectively. Y

ln the event a powdered detergent is employed,A water f-may befintrodfucedintothe container 52 from the line 4t) by wayof a pipe A6I?. having asolenoid valve whose solenoidV is designated by the numeral of. valve in the line lil between the line 42. and pipe 62, has aV solenoid designated by the numeral 66.

"A1 timer shown*schematically'v in Fig. '2 includes a v" timer motor 68 operablyy coupled with a cam shaft 7i) j upon which is mounted a plurality of cam discs, discs 72- and` 74I being associated withv the solenoid 28, discs 76 and 7% being adapted' .tof control.. the solenoid 66, disc 80 having an operablel connection with solenoidy 58,

disc 82- correspondingv to the solenoids 61k` and 64, vand disc 84 controlling the motors .34 and 65.

Normally open` switches 72a, 7602,74@ title, 82a,

on shaft 70 forclosing upon register with thevarious indentations provided at the peripheries of the said discs.

:The disposition and lengths of such indentations inthe ydiscs may besty be understood by viewingthe .chart eacha seconds. fore, pump 32, recirculates the liquid in the system from vat` 10, through drain i8, valve body 2i?,A line 36, pump 32, lineSS, and manifold :16, to wash away loose foreign?` `material, on the dishes. within tray i4, for a period of approximately six seconds. Thereupon, cam discySZl closes switch` 82a, to inv turn energize solenoid 6G fonia Vperiod of approximately three seconds, as indicated lby shadedvarea 92, to admit detergent from the 'container j 52, through pipe 56 and into the. vat itl.'

The detergent-admixes with the circulating liquidpresenting a water-.detergent admixture' which is sprayed over the. dishes inthe tray 14.k After the machine has oper-YA ated lfor approximately 55 seconds, disc 74 closes switch 1 74a to energizesolenoid Z8 for approximately 13 seconds as indicated by shaded area 94 in Fig. 1,1, during which time the waterfdetergent admixture drains past valve 2d intofpipe 22. Although the pump 32 is still operating, itA

isseen that, while the liquid. is' beingdrained from the-V vat it?, .there will be no ilow'inl the line 35, and,1there fore, all filtered material collected kon the inner surface A solenoid rsa. and 84a. are -disposedfadjacent the corresponding discs in line 40 is opened by virtue of the operation' of disc 78, closing switch 78a and energizing solenoid 66, thereby admitting fresh water into the vat either by way of pipe 42 or pipe 46, depending upon which of the valves 44-48 is open. Y

After the machine is completely flushed clean of Waterdetergent admixture, valve 24 re-closes and solenoid 66 remains energized for an additional 20 seconds, as indicated by shaded area 96 in Fig. 1. However, while water is being admitted into the vat 10, disc 80 will have moved to a position closing switch 80a, thereby energizing solenoid 58 and causing a sterilizer to ow into vat 10 by gravity through pipe 54. As indicated by shaded area 98 in Fig. 1, solenoid 58 remains energized for approximately three seconds.

The water-sterilizer admixture is recirculated over the Adishes in tray 14 until the machine is operated for a total of 120 seconds, whereupon disc 72 closes switch 72a, thereby energizing solenoid 23 and again opening the valve 24 for a period of thirteen seconds as indicated by shaded area 100 in Fig. l. As soon as valve 24 recloses, the water valve in line 40 is again re-opened by energization of solenoid 66 because of the fact that disc 76 has opened switch 76a.

The water valve remains open for a period of twenty seconds, as shown by shaded area 102 in chart 90. The water thus admitted into the vat 10 is recirculated until the completion of the cycle when switch 84a reopens and such water is utilized in the next cycle of operation for iinshing foreign matter from the dishes and for admixture with detergent emanating from container 52 when the solenoid 60 is energized because of the closing of switch 82a.

In the event it is desired to direct water into the detergent container 52 upon closing of switch 82a, a manual switch 104 in series with the solenoid 64, is closed, it being noted that switches 72a and 104 are likewise coupled in series.

Oftentimes, by virtue of the aforedescribed cycle, the recirculation system becomes air-logged and, therefore, it becomes desirable to momentarily deenergize the motor 34. This is accomplished by utilizing a normally closed switch idd which opens and remains open for three seconds during the energization of solenoid 58 through closing of switch 80a.

When switch 113 is in the position shown in Fig. 2, closing of manual switch 87 energizes timer motor 68. It also energizes coil 107 of relay 109 to close switch 111 of the latter. This energizes motor 34 through switch 111. As soon as disc 84 rotates to close switch 84a, motor 63 and coil 107 remain energized even after opening of switch 87 until switch 84a re-opens.

However, when switch 113 is placed in series with switch 106 (while switch 80a is open) coil 107 is energized to energize motor 34. through switch 111. When switch 87 is closed, motor 68 operates to cause closing of switch f Sita to permitV opening of switch 87. As soon as switch 80a closes, switch 106 opens, thereby deenergizing motor 34 for three seconds.

Many governmental codes do not permit the rinsing away of the sterilizing solution from the dishes as provided in the above cycle. Accordingly, in Fig. 3 of the drawings, there is shown a chart 10S contemplating a two and one-half minute cycle, wherein the opening of valve 24, as indicated by the shaded area 100, and the re-introduction of water as shown by shaded area 102, are eliminated. lt is seen that under such circumstances the sterilizerwater admixture is retained at the end of each cycle and utilized with the detergent in the next succeeding cycle.

In comparing charts 9i) and 108, it is seen that in the latter, the period of time for cleansing the dishes with the detergent water, is increased by approximately fifteen seconds, and that the dishes are actually sterilized for 4 eighteen additional seconds notwithstanding the fact that the cycle of chart 108 is thirty seconds shorter than the cycle of chart 90.

Another embodiment is depicted by chart 110 in Fig. 4 that employs the same time cycle as shown in chart so far as rinsing the dishes with detergent water is concerned and also in sterilizing the dishes. However, as contemplated by chart 108, the sterilizer water is here again utilized in the next cycle of operation for receiving the detergent.

Having thus described the invention what is claimed as new and desired to be secured by Letters Patent is:

1. A method of cleaning and sterilizing soiled dishes which comprises interposing said dishes to be cleaned and sterilized within the normally closed circuit of a waterrecirculation system; gravitationally directing a detergent into said system for admixture and circulation with the water; opening said circuit after a predetermined period of time to drain the water-detergent admixture therefrom; introducing a predetermined amount of rinse water into said system after draining for a predetermined period of time while the system continues to operate and while the circuit is open whereby to remove the admixture from the dishes and ush the same from the system; reclosing the circuit after a predetermined period of time; gravital tionally directing a predetermined quantity of sterilizer into said system while continuing to introduce rinse water; discontinuing introduction of rinse water; and discontinuing the recirculation of the water-sterilizer admixture after a predetermined period of time following completion of the rinse water introduction.

2. A method of cleaning and sterilizing soiled dishes which comprises interposing said `dishes to be cleaned and sterilized within the normally closed circuit of a continuously operating, water-recirculation system; gravitationally directing a detergent into said system for admixture and circulation with the water; opening said circuit after a predetermined period of time to drain the water-detergent admixture therefrom; introducing a pre determined amount of rinse water into said system after draining for a predetermined period of time while the system continues to operate and while the circuit is open whereby to remove the admixture from the dishes and llush the same from the system; reclosing the circuit after a predetermined period of time; gravitationally directing a predetermined quantity of a sterilizer into said system while continuing to introduce rinse water; discontinuing introduction of rinse water; discontinuing the recirculation of the water-sterilizer admixture after a predetermined period of time following completion of rinse water introduction while the circuit is closed; and retaining said rinse water-sterilizer admxture Within said closed system whereby the rinse water-sterilizer admixture retained in the system is used in the water-detergent admixture of the next succeeding cycle of operation.

3. A method of cleaning and sterilizing soiled dishes which comprises interposing said dishes to be cleaned and sterilized within the normally closed circuit of a water-recirculation system; gravitationally directing a detergent into said system for admixture and circulation with the water; opening said circuit after a predetermined period of time to drain the water-detergent admixture therefrom; introducing a predetermined amount of rinse water into said system after draining for a predetermined period of time while the system continues to operate and while the circuit is open whereby to remove the admixture from the dishes and flush the same from the system; reclosing the circuit after a predetermined period of time; gravitationally 'directing a predetermined quantity of a sterilizer into said system while continuing to introduce rinse water; discontinuing recirculation while introducing the sterilizer; resuming recirculation to rinse the dishes with water-sterilizer admixture; discontinuing introduction of rinse water; discontinuing the recirculation of the Water-sterilizer admixture after a predetermined period of time following completion of rinse Water introduction while the circuit is closed; and retaining said rinse water-sterilizer admixture within said closed system whereby the rinse Water-sterilizer admixture retained in the system is used in the water-detergent admixture of the next succeeding cycle of operation.

4. A method of cleaning and sterilizing soiled dishes which comprises interposing said dishes to be cleaned and sterilized within the normally closed circuit of a continuously operating, water-recirculation system; gravitationally ydirecting a detergent into said system for admixture and circulation with the water; opening said circuit after a predetermined period of time to drain the water-detergent admixture therefrom; introducing a predetermined amount of rinse water into said system after draining for a predetermined period of time while the system continues to operate and while the circuit is open whereby to remove the admixture from the dishes and ush the same from the system; reclosing the circuit after a predetermined period of time; gravitationally directing a predetermined quantity of a sterilizer into said system while continuing to introduce rinse water; discontinuing introduction of rinse water; opening said circuit after a predetermined period of time following completion of rinse water introduction and until the water-sterilizer admixture is drained therefrom; reclosing the circuit; introducing a predetermined amount of water into the system for subjecting the dishes to a second rinse; discontinung the recirculation of the second rinse water while the circuit is closed; and retaining said second rinse water within said closed system whereby said second rinse water retained in the system is used in the water-detergent admixture of the next succeeding cycle of operation.

5. A method of cleaning and sterilizing soiled dishes which comprises interposing said dishes to be cleaned and sterilized within the normally closed circuit of a water-recirculation system; gravitationally directing a de- 6 tergent into said system for admixture and circulation with the water; opening said circuit after a predetermined period of time to drain the water-detergent admixture therefrom; introducing a predetermined amount of rinse water into said system after draining for a predetermined period of time while the system continues to operate and while the circuit is open whereby to remove the admixture from the dishes and flush the same from the system; reclosing the circuit after a predetermined period of time; gravitationally directing a predetermined quantity of a sterilizer into said system While continuing to introduce rinse water; discontinuing recirculation while introducing the sterilizer; resuming recirculation to rinse the dishes with water-sterilizer admixture; discon# tinuing introduction of rinse water; opening said circuit after a predetermined period of time following compley.

tion of rinse water introduction and until the watersterilizer admixture is drained therefrom; reclosing the circuit; introducing a predetermined amount of water into the system for subjecting the dishes to a second rinse; discontinuing the recirculation of the second rinse Water while the circuit is closed; and retaining said second rinse water within said closed system whereby said second rinse water retained in the system is used in the Water-detergent admixture of the next succeeding cycle of operation.

References Cited in the' tile of this patent UNITED STATES PATENTS 1,737,794 Henderson Dec.v3, 1929 2,025,571 Clark Dec. 24, 1935 2,275,189 Y Wieghart ...7.... Mar. 3, 1942 2,385,264 Ferris Sept. 18, 1945 2,390,757 Voris Dec. 11, 1945 2,642,369V Hunter June 16, 1953 2,718,481 Tuthill Sept. 20, 1955

Claims

1. A METHOD OF CLEANING AND STERILIZING SOILED DISHES WHICH COMPRISES INTERPOSING SAID DISHES TO BE CLEANED AND STERILIZED WITHIN THE NORMALLY CLOSED CIRCUIT OF A WATERRECIRCULATION SYSTEM? GRAVITATIONALLY DIRECTING A DETERGENT INTO SAID SYSTEM FOR ADMIXTURE AND CIRCULATION WITH THE WATER? OPENING SAID CIRCUIT AFTER A PREDETERMINED PERIOD OF TIME TO DRAIN THE WATER-DETERGENT ADMIXTURE THEREFROM? INTRODCING A PREDETERMINED AMOUNT OF RINSE WATER INTO SAID SYSTEM AFTER DRAINING FOR A PREDETERMINED PERIOD OF TIME WHILE THE SYSTEM CONTINUES TO OPERATE AND WHILE THE CIRCUIT IS OPEN WHEREBY TO REMOVE THE ADMIXTURE FROM THE DISHES AND FLUSH THE SAME FROM THE SYSTEM? RECLOSING THE CIRCUIT AFTER A PREDETERMINED PERIOD OF TIME? GRAVITATIONALLY DIRECTING A PREDETERMINED QUANTITY OF STERILIZER INTO SAID SYSTEM WHILE CONTINUING TO INTRODUCE RINSE WATER? DISCONTINUING INTRODUCTION TO RINSE WATER? AND DISCONTINUING THE RECIRCULATION OF THE WATER-STERILIZER ADMIXTURE AFTER A PREDETERMINED PERIOD OF TIME FOLLOWING COMPLETION OF THE RINSE WATER INTRODUCTION.